h2. Configuration
-Add entries to @InstanceTypes@ that have @Preemptible: true@. Typically you want to add both preemptible and non-preemptible entries for each cloud provider VM type. The @Price@ for preemptible instances is the maximum bid price, the actual price paid is dynamic and will likely be lower. For example:
+First, configure some @InstanceTypes@ that have @Preemptible: true@. For a preemptible instance, @Price@ determines the maximum bid price; the actual price paid is dynamic and will likely be lower.
+
+Typically you want to add both preemptible and non-preemptible entries for each cloud provider VM type. To do this automatically, use @PreemptiblePriceFactor@ to enable a preemptible version of each listed type, using the given factor to set the maximum bid price relative to the non-preemptible price. Alternatively, you can configure preemptible instance types explicitly. For example, the following two configurations are equivalent:
<pre>
Clusters:
ClusterID:
+ Containers:
+ PreemptiblePriceFactor: 0.8
InstanceTypes:
m4.large:
- Preemptible: false
ProviderType: m4.large
VCPUs: 2
RAM: 8GiB
AddedScratch: 32GB
Price: 0.1
- m4.large.spot:
- Preemptible: true
+</pre>
+
+<pre>
+Clusters:
+ ClusterID:
+ InstanceTypes:
+ m4.large:
ProviderType: m4.large
VCPUs: 2
RAM: 8GiB
AddedScratch: 32GB
Price: 0.1
+ m4.large.preemptible:
+ Preemptible: true
+ ProviderType: m4.large
+ VCPUs: 2
+ RAM: 8GiB
+ AddedScratch: 32GB
+ Price: 0.08
</pre>
Next, you can choose to enable automatic use of preemptible instances:
<pre>
+Clusters:
+ ClusterID:
Containers:
AlwaysUsePreemptibleInstances: true
</pre>